Stocks were broadly lower Monday, with most of the damage done in the Nasdaq. The market opened lower on a disappointing holiday weekend for retailers and Chinese economic data. The Nasdaq finished down 1.3%, the S&P 500 fell 0.7%, and the Dow Jones industrial average dropped 0.3% in the stock market today. Volume was well above the pace of Friday’s half session, according to preliminary data. MattressFirm (MFRM) was volatile after hours.